<p>The 5 m diameter 23.3 km long Yacamb&uacute;-Quibor tunnel is designed to carry water through the Andes from the Yacamb&uacute; dam in the wet tropical Orinoco basin to the semi-arid but fertile Quibor basin in western Venezuela. The tunnel is excavated ...

<p>This paper describes the methods that can be used to optimize the design of tunnels using a combination of reinforcement and support methods. Particular attention is given to tunnels in very weak rock or soil in which large deformations can occur. Two case ...